.lanren {
    width: 500px;
    height: auto;
    margin: 0 auto;
    overflow: hidden;
    text-align: center;
}

.lanren #qrcode {
    width: 200px;
    height: 200px;
    position: relative;
    margin: 10px auto;
    display: none;
}

.lanren input {
    width: 200px;
    height: 20px;
    line-height: 20px;
    padding: 4px;
    outline: 0;
}

.lanren button {
    display: block;
    width: 120px;
    height: 45px;
    background: #0cc;
    text-align: center;
    line-height: 45px;
    border-radius: 45px;
    margin: 5px auto;
    border: none;
    cursor: pointer;
    color: #fff;
    outline: 0;
}